Can an Unhealthy Relationship Cause a Mental Breakdown?

Relationships can be complicated, and even strong, healthy relationships take work and can, at times, cause stress. So many of us have grown up being taught to prize loyalty, to stick it out when times get tough, and to “make it work.” But what about deal breakers?

What happens when you ask yourself, “Am I in a toxic relationship?” or tell yourself that your wife’s or husband’s “mental illness is killing me.” How much relationship stress caused by toxic traits should you reasonably tolerate, and could sticking it out in an unhealthy relationship cause you to suffer mentally, even to suffer a mental breakdown?

Stress comes in many different forms, including short, tall, blond, brunette, etc. Yes, people can be extremely stressful, and toxic, unhealthy relationships are common triggers for substance abuse. Of course, self-medicating is never a good idea, no matter the stressor, but feeling driven to drink isn’t the only risk of an unhealthy relationship. Depending on the situation and level of toxicity involved, as well as one’s own capacity for coping with stress, an unhealthy relationship can worsen or even cause mental health issues.

How Do You Determine if a Relationship Is Unhealthy?

Read nearly any self-help magazine and you’re likely to find relationship tests titled along the lines of “Am I in a Toxic Relationship?” On paper, toxicity seems easy enough to diagnose, but in reality, many people don’t even realize that their relationship is not just a little unhealthy but extremely unhealthy. So, how can you gauge a relationship’s health?

First, consider your feelings. How often do you experience negative emotions such as anger, fear, sadness, or loneliness? Try to mentally calculate how often you feel these emotions, as opposed to positive emotions like contentment and joy. If your emotions are heavily on the negative side, it’s important to determine why. Is it you–something you can’t put your finger on? Is it your job? Or is it your relationship?

Characteristics of Healthy vs. Unhealthy Relationships

Although each relationship is unique, both healthy and unhealthy relationships share certain characteristics. For instance, a healthy relationship involves mutual respect, trust, and peaceable conflict resolution. In contrast, an unhealthy or toxic relationship may involve:

• Insensitivity
• Disrespect
• Criticism
• Insecurity
• Mistrust
• Physical or emotional abuse

Underlying Issues and the Impact of Unhealthy Relationships

Unhealthy relationships don’t come from out of nowhere. Sometimes, one partner deals with mental health struggles or addiction. Past trauma, especially from childhood, can leave deep scars that shape how they connect with others. Trust issues, insecurity, and harmful behaviors often follow.

Love doesn’t always disappear just because a relationship turns toxic. That’s what makes it so hard to walk away. Stress from a difficult relationship doesn’t just stay in one part of life. Over time, it wears down mental and physical health, and the weight of it seeps into everything.

What Is a Mental Breakdown?

Stress stacks up. Pressure builds. At some point, the weight feels unbearable. That’s a mental breakdown.

It’s not a medical diagnosis, just a way to describe a moment when everything feels like too much. Exhaustion, anxiety or depression—sometimes all three—hit at once. Work, relationships, money, grief. Stress doesn’t care where it comes from. It just keeps coming until something gives.

This kind of emotional collapse doesn’t have a single cause. It can stem from pressure at work, grief, financial strain, or a toxic home life. Whatever the trigger, the result is the same: a feeling of being trapped, powerless, and sometimes even suicidal. Some people break down in tears that won’t stop. Others go numb, shutting down emotionally. Routine tasks—getting out of bed, eating, answering a text—can feel impossible.

A mental breakdown isn’t just having a rough day. It’s reaching a breaking point where coping skills fail, and everything feels unmanageable.

Can Stress Cause a Mental Breakdown?

A mental breakdown is generally triggered by an intense degree of stress. In fact, the breakdown is an intense reaction to the stress caused by symptoms of anxiety or depression. But what causes anxiety and depression? Some people are genetically predisposed to these conditions–as if they’re hardwired that way. Some people may be vulnerable because of past trauma or because of their high-stress professional or personal life.

When the symptoms of a mental health disturbance are left unchecked and veer into a full-blown mental health condition or disorder, treatment is needed, but many people don’t seek treatment. Their feelings of depression may be unpleasant but manageable. However, as a mental health condition continues, the continued stress it causes can wear a person down until they are left feeling completely overwhelmed. This untreated mental health condition can be one of the causes of mental breakdown.

What Should You Do If an Unhealthy Relationship Is Pushing You to the Breaking Point?

No one should deal with this alone. A doctor or therapist can help sort out what’s happening—sometimes that means counseling, sometimes medication, sometimes both. Relationship therapy might also be an option. The important thing is taking that first step, even if it feels impossible. Stress like this doesn’t just sit quietly in the background. It creeps into everything—work, sleep, health. Getting help isn’t about fixing the relationship. It’s about making sure stress doesn’t break you down.

Seek Help and Prioritize Safety

For someone feeling overwhelmed, the idea of picking up and leaving a relationship may feel even more overwhelming, but in cases where abuse is involved, that may be the answer. First, consider your personal safety. If you feel unsafe, you should seek safety.

Address the Underlying Issues

Coping with relationship stress can also depend on the issues at hand. If your partner has a substance abuse issue, are they in treatment? Are they willing to get help or are they in denial? Is your partner cheating on you or are you struggling with your own suspicions or insecurities? Do you feel like you walk on eggshells around your home because your partner is under stress and has an anger management problem?

The Importance of Action

Many issues in an unhealthy relationship can be resolved when both people are determined to face them and work on them. A major reason why chronic relationship stress occurs is because one or both parties are unwilling to address issues and neither has decided to end the relationship for whatever reason–and there are often important reasons (love, kids, financial constraints, etc.). However, the longer a relationship remains unhealthy, the greater the risk that it will continue to take an emotional toll and cause a mental breakdown.

Don’t Weaponize Your Mental Health in a Relationship

Some people weaponize their mental health condition in their relationship or weaponize their partner’s mental health. For instance, the term “narcissist” is frequently batted about to describe anyone with whom one has had a bad relationship with. It’s important to distinguish between a toxic relationship and a relationship in which two people just don’t click. Calling a person a narcissist because they have a tendency to want their own way isn’t always fair and could be an example of weaponizing.

Conversely, if you have anxiety or depression, it may not be completely accurate to say that your partner or spouse caused it. Again, relationships, like mental health, are complex. Often, it’s the behavioral patterns of both people that lead to conflict. Moreover, a person may be vulnerable to anxiety or depression and, as such, are more vulnerable to the effects of stress.

When to Seek Outside Help

The best time to ask for help is after a few weeks have gone by and you’re still feeling symptoms of anxiety or depression. When you’re feeling stressed out more often than you feel content, it’s important to seek an evaluation. When you seek help from a therapist or counselor, they’ll help you identify exactly what’s causing your stress and help you develop strategies for coping with it. Once you get help and begin to feel better, you may feel more capable of coping with your relationship issues.

On the other hand, your relationship may be so unhealthy that making changes is in your best interest, and in that case, a counselor can help you develop a plan for working things out in your relationship or ending it. In any case, expect your therapist or doctor to empower you to make your own healthy decisions, choosing what’s best for you.

If you are in an unhealthy relationship and it is making you feel worse on a regular basis, talk to a professional and get some advice. You don’t have to do it alone.